1. Field of the Invention
The present invention is directed to the field of wedge base lamp sockets and more particularly to the area of an improved socket assembly.
2. Description of the Prior Art
It is commonplace to find wedge base electric lamps used for illumination of display panels such as in the instrument panels of automotive vehicles. The socket assemblies used to support the replaceable lamps are, for the most part, insertable into an aperture of a rigid support panel. The support panel contains an overlay of a flexible printed circuit layer with exposed portions of electrical conductors adjacent the aperture so that the corresponding electrical contacts on the socket assembly will be compressibly mated when the socket is properly inserted into the aperture and latched therein.
U.S. Pat. Nos. 3,909,096 and 4,227,760 illustrate typical socket assemblies which are utilized in conjunction with flexible printed circuit layers. In each case, the sockets are inserted through aligned apertures in the printed circuit layer and the rigid support panel. Latching is achieved by rotating the socket assembly a prescribed amount after it is fully inserted so that locking shoulders extending from the forward portion of the socket assembly will latch to the opposite surface of the rigid support panel. Open notches are included in the periphery of the panel aperture in order to allow the locking shoulders to pass during insertion and prior to latching rotation.
British Patent Specification No. 1,454,509 illustrates a common type of socket assembly that is ideally suited for automated assembly since the socket is inserted into the aperture of the rigid panel and is latched therein without further rotation of the socket. That device employs a flexible printed circuit layer having exposed conductor portions which extend over the aperture formed in the support panel so that insertion of the lamp socket causes the exposed conductors to be wiped down into and against the internal sidewalls of the aperture. Electrical contacts of the socket are biased outwardly and compress the electrical conductors against the aperture sidewalls to maintain electrical contact. Removal of the socket device is achieved by pushing or pulling the socket in the reverse direction of its insertion so as to overcome the friction fit of the conductors and adjacent resilient members.
In each of the prior art examples cited above, the flexible printed circuit layer is located on the same side of the rigid support panel as the lamp socket assembly is inserted into the panel aperture. Likewise, removal of the socket assembly is achieved by gaining access to the same side of the rigid panel in which the flexible printed circuit layer is located in order to release the locking mechanism and withdraw the assembly. As a result, when rear panel access is desired to allow removal of the lamp socket assembly, the flexible printed circuit layer must also be located on the rear surface of the rigid support panel.